A ringless voicemail drop places a pre-recorded message into a phone’s voicemail inbox without the phone having to ring. The technology sends the voicemail message directly into the recipient’s voicemail server. PhoneBurner does not offer ringless voicemails.
You could add the words "After-Hours Service" or "After-Hours Line" after the company's name. That way there's no concern over whether it is indeed a number that reaches a real person who will return their call during non-business hours. It's a way to let them know they're on the right track. If that makes sense. :)

Menu Create phone greeting audios using Text To Speech (TTS) services 29 May 2018 on ivr, Greeting audios. When you use a virtual phone system such as Toky, you have many features available like greeting messages.The audios are the way your phone system interacts with your callers and it is important to configure them properly.
For a medical office, call types may include billing, emergencies, appointments, cancellations, etc. 2. Determine How To Best Route Calls The best method of routing your medical office calls will depend on your office size and budget. If you have a small staff, setting up a standard voicemail greeting system may be a more practical approach. For a larger health organization with multiple departments, it makes more sense to route calls to their intended destinations by using an auto attendant. For example, “If you have a question about billing, press 1. If you’d like to schedule an appointment, press 2. If this is a medical emergency, press 0 for an operator.” If you want every caller or patient to experience a professional and compassionate call, you may consider working with a medical office answering service. You can forward calls to an answering service after business hours, on holidays, during overflow, or any other time you may need help answering calls. 3. Draft A Script